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Discussion in 'Personal' started by lexus300, Mar 19, 2019.
17 or 53 years is less than a dot in geological time.
Some undoubtedly are.
Spread with fraud in mind IMO.
What do you call data manipulation and/or omission of data that does not fit the model?
It has been measured/observed.
I do not know what the true level of global warming is, nor do the modellers, they know what they want it to be and therein lies the rub.
The world is increasing its greening and may as a result cool.
lexus seems to have a found a website to help him to cite a few cherry-picked papers that on the face of it could appear to back up his favoured conclusion.
All in the region of 15-20 years old however and none actually go against the concept of AGW.
CO2 is far too low to affect the climate
CO2 increases are causing massive changes in plant growth.
How can anyone possibly tell what the temperature or CO2 levels were thousands of years ago?
Thousands of years ago CO2 was higher than now and the temperature varied like this....
We can't measure the temperature accurately enough.
...apart from these examples that I reckon show definitively there is cooling.
Disgruntled former materials scientist who worked for NASA (!) and his video on youtube - or some bloke in his car making a video - or oil industry funded mouthpiece trying to make some money in retirement (medical bills are expensive in the USA).
(doffs cap to rac for this last one)
There are upper limits because CO2 uptake is not an isolated factor.
And increased CO2 means increased temperatures, leading to lower yields as a result of climate change.
This has been quantified as a % reduction per degree of warming for several staple crops.
What about the increased water demanded by the increased plant tissues, never mind the increased photosynthesis itself?
There is an enormous difference between increasing CO2 levels under covers for crops and allowing atmospheric CO2 levels to rise to the same extent. Greening includes plant life which is not controlled below covers or in sprayed fields so these non-crop plants act as reservoirs for other pests which might then require heavier application of pesticides.
Professor Medlyn stressed that the experiment had analysed extra CO2 only “at the leaf scale”, with more work needed to observe the effects on whole plants and communities. Hotter conditions would probably cancel out benefits of higher CO2.
Matt Ridley didn't mention this although it was in his link.
About 8,100 plant species use C4 carbon fixation, which represents about 3% of all terrestrial species of plants. All these 8,100 species are angiosperms. C4 carbon fixation is more common in monocots compared with dicots, with 40% of monocots using the C4 pathway, compared with only 4.5% of dicots. Despite this, only three families of monocots use C4 carbon fixation compared to 15 dicot families. Of the monocot clades containing C4 plants, the grass (Poaceae) species use the C4 photosynthetic pathway most. 46% of grasses are C4 and together account for 61% of C4 species. These include the food crops maize, sugar cane, millet, and sorghum. Of the dicot clades containing C4 species, the orderCaryophyllales contains the most species. Of the families in the Caryophyllales, the Chenopodiaceae use C4 carbon fixation the most, with 550 out of 1,400 species using it. About 250 of the 1,000 species of the related Amaranthaceae also use C4.
Raises the issue of food plants. Maize, millet and sorghum are important but if, as Ridley says, these are hampered by increasing CO2 it is a problem.
...and more advantage to C3 plants at the expense of C4 plants. Many crop plants are C4, many weeds are C3.
But pineapples are CAM, so they should be OK.
Rhubarb is a good waste of CO2.
Yes. The amount of warming in that dot of geological time is the point.
No it won't. Not a chance.
The irony of this statement:
will only be lost on one person.
You couldn't make it up.
It can't - the greenhouse gas layer is here to stay.
We had better hope so!
My references are not from the internet directly, I have checked them out on the internet however.
What you fail to understand is that to use CO2 as the culprit for AGW you need look back to when the most recent global warming commenced and that was a very long time ago for us but insignificantly small in geological terms.
The earth came out of the little ice age some 300 years ago and the little ice age lasted from around 1400 to 1700 and that was preceeded by the medieval warm period which lasted for close on 500 years. (source: Loehle 2008ab) It should be noted that todays temperatures are still well below those of the medievel warming period peak.
Anyway, we have had a 300 year warming period which shows a virtually consistent and relatively steady total rise in temperature of 1.5 degC over 300 years. Source: Parker 1992 and Boden 2016. It is not hidden that our more recent CO2 additions started just after WW2 and the rate of temperature increase in that 70 year period (within the 300 years) is not noticeably different to what happened pre-industrialisation.
I know this goes against the infamous and fraudulent hockey stick graph by Mann so often used by the IPCC in their assessment reports and conferences. If you want to know why it is fraudulent let me know and I will tell you.
If they grow faster on less water is there an actual increased water demand?
Who knows and if so at what point bearing in mind that plant life thrived for millions of years on much higher levels of atmospheric CO2 than at presnt?